The case of a former Jersey City police sergeant who claimed she was not promoted because she worked for a challenger of Mayor Jerramiah Healy in the 2004 special mayoral election may go to a jury trial, an appellate court has ruled.

The March 8 ruling overturns a lower-court decision that tossed the suit, which was filed by former sergeant Valerie Montone and eight others against the city, Healy and former Police Chief Robert Troy.

The lower-court erred by making credibility determinations about evidence that a jury should make, the three appellate judges ruled. In addition, the judges say in their ruling, there is “a reasonable inference that Montone was not promoted in retaliation for her political activity.”

In the 2004 election, 11 candidates vied to fill out the term of the late Glenn D. Cunningham, who died the previous May. Montone worked for the campaign of former Assemblyman Lou Manzo, who came in second, finishing with about 2,000 fewer votes than Healy.

Montone claims Healy and Troy purposely didn’t promote anyone to lieutenant because she was fifth on a list of 39 officers set to become lieutenants.

She sued in state court in 2005, claiming political retaliation and violations of the First Amendment. The suit moved to federal court the following month, and in August 2006, the eight other plaintiffs joined Montone, saying the city’s alleged retaliation against her kept them from being promoted.

A number of witnesses gave deposition testimony that all promotions from sergeant to lieutenant were halted to retaliate against Montone, who retired as sergeant in 2010, the ruling states.

The city argued that there was no retaliation, and that the shortage of lieutenants at the time, there were 30, even though the state authorized over 60 was the result of budgetary concerns.

In June 2011, a federal district court judge tossed the suit, handing Jersey City a win that the appellate court has now overturned.

“This opinion means that the appellate court disagreed with the trial judge by finding that there are issues of fact that a jury should decide, but we remain confident that when a jury does hear the facts, that the plaintiff’s claims will again be rejected, as they were by the trial judge,” said Corporation Counsel Bill Matsikoudis.